The completion of the human genome project pushes us towards the next daunting task; namely that of translating sequence information into functional information. As in the case of the sequencing effort, this will necessitate innovative biological approaches combined with the development of new technologies. Approaches to functional genomics include whole genome deletion and mutation studies in model organisms as well as high-throughput mapping of complex traits in both human and model organisms through the use of polymorphism detection and resequencing. We propose to develop new functional genomics approaches to the study of Saccharomyces cerevisiae and human. Studies in S. cerevisiae employ a complete collection of bar coded yeast deletion strains for quantitative phenotypic analysis of fundamental cellular pathways as well for the identification of inhibitory compounds that act against every novel essential gene product. Other approaches to the elucidation of gene function and cellular pathways include mapping of complex traits using dense marker maps, the synthesis of every possible single base/amino acid mutation in any gene of choice, and the use of mass spectrometry to identify all small metabolites. We propose to extend these studies to human through genome-wide scanning for mutations and splicing defects. These ambitious goals will only be attainable through technological innovation in the areas of higher throughput sequence determination techniques (Pyrosequencing, HPLC, barcoded genotyping), low cost oligonucleotide and gene synthesis, and microarray automation and cost reduction. In addition, bioinfonnatics tools and databases that allow the integration of a large amounts of diverse data structures will need to be developed in order to maximize the deconvolution of vast amounts of biological data into biological function. All of these components will be tested in an implementation project to validate the technology and to enable its export from our laboratory.